I'm So Sorry
by The Queen of Double Standards
Summary: Rin is in love with Lui, but he's dating her best friend, Ring. Then, one day, she kissed him, and the affair has continued to this day. Rin hates herself, but she can't resist. RinxLui oneshot


**Author's Note: Rin, Ring, and Lui are all the same age in this fic.**

**I'm So Sorry**

_And now I'm sick inside  
><em>_Yeah, it makes me wanna cry  
><em>_I'm so sorry about last night  
><em>_Yeah, it happened so fast  
><em>_I wanted it to last  
><em>_In the moment it felt so right  
><em>_But now I'm sick inside_

-Sick Inside by Hope Partlow

"_Lui?" Rin asked quietly, leaning toward him from where they sat in the darkened movie theatre, her face bright red. The movie continued playing, but she was completely oblivious to it at this point. "Can I ask you for something?"_

"_Sure, anything," he agreed, catching onto her seriousness and echoing it perfectly, staring at her curiously. He didn't seem to care for the movie, much, either. It had been Ring's choice, after all, and she always went with the sort of gooey romantic chick flicks that neither Rin nor Lui were interested in._

_Rin gulped, knowing full well that what she was doing was horrible. Lui's girlfriend, and her best friend, was only minutes away, in the bathroom. Still, watching this movie, being alone with him, Rin couldn't help herself. "I've never kissed anyone before," she ventured, staring at him, her heartbeat racing. "So, can I, you know, ask you to . . ."_

"_S-sure," he stammered, his face burning bright red. He stared right at her, and she could've sworn that he wanted it just as much as she did. "Just don't tell Ring, okay?"_

"_O-okay," Rin replied, too overjoyed to remember what a horrible person she was._

. . .

"It's not fair," Rin murmured into her pillow as she hid in her bedroom, the lights all turned off. She felt like she should cry, but she couldn't muster up any tears. She'd been locked up in her room for the last two days, skipping school, claiming to be sick. But she wasn't. She just couldn't handle it, being at school. After all, she had to see _him_ there, and, even worse, _her_. The memories of what she'd done made her feel sick.

Rin looked desolately at her phone as it vibrated, picking it up when it continued shaking her bed. The caller ID warned her not to answer, despite the butterflies fluttering in her stomach and the joy the name brought her. But she didn't want to answer. She couldn't do it.

But she couldn't resist, either.

"Hello?" she croaked, her throat dry, as she answered. She cleared her throat and tried again. "Hello?"

"Where are you, Rin?"

Lui. Rin squeezed her eyes shut, pushing down the joy that came from hearing him speak and letting the guilt take over. Why did it have to be him? Why couldn't somebody else have been the one calling her? Anyone but him. "I'm sick. I'll be back next week, I guess."

Lui would have none of it. He was so overly-cheerful that Rin was certain he'd forgotten about their kiss at the movies, despite the fact that it meant so much to her. "No way, Rin! You'll be back now! Look out your window!"

"Lui, I can't," she whispered, trying to fight back the triumphant feeling that his words gave her. He'd come to visit her while she was 'sick'.

"C'mon, Rin, sitting around in bed's not going to help you!" he argued. Rin was pretty sure he was pouting about now. "You have to get out and get some fresh air! Ring's really missing you!"

The triumph faded. Of course. Ring. His girlfriend, and her best friend. Obviously, she'd be there, too. Rin pulled herself off her bed, peeled back her curtains, and peered out the window to where Lui stood, leaning against his car. He smiled and waved at her. She didn't see Ring, so she asked where she was. Lui peered around himself and laughed. "I wish I knew," he said. "I really don't know where she is, but she said she'd meet us wherever we decide to go. I'm gonna come up and see you, okay?"

"Lui, I don't want to be alone with you," Rin said hurriedly, panicking.

"Calm down, Rin," he laughed, looking up at her curiously. "We're friends, aren't we?" Then, his gaze grew a little darker as he met her guilt-filled eyes. "Oh, that. It didn't mean anything, right? Nothing's going to happen. You don't have to worry."

Rin couldn't say anything to that, especially considering how much hearing it made her traitor-heart ache. Honestly, what _could_ she say to that? You can't come up because I'm in love with you? No. So she had to give in when Lui hung up on her, entered her house, and met her up in her room.

Rin was forced to pretend as though nothing was wrong, and it killed her. At first, it was all innocent, just pointless chatter and playful banter. They were friends, after all. Then, something happened that should have never happened.

"You're such a moron," Rin scoffed, leaning in toward him, her eyes glittering mischievously. "You seriously think you stand any chance against me? I'll beat any high score you make at the arcade the moment you make it, got it?"

"Is that so?" he challenged, leaning into her with a smirk, their faces now but inches apart. "You really think you're that good? I'd like to see you try."

"How about tomorrow?" Rin offered, her eyes sparkling competitively.

"It's a date," he agreed, his choice of words bringing both of them to their senses. They quickly drew away from each other, realizing what they were doing.

Rin peered up at him, wondering if he was watching her. He was. She quickly averted her gaze, trying to deny the longing in his eyes. She squeezed her eyes shut, locking back the tears that were forming.

"Rin," came his voice. She couldn't resist looking up at him, no matter how terrible it was. She turned her head toward him, and his crooked finger came under her chin, making her heart stutter and her eyes lock on his.

"Lui," she murmured, unable to look away as her heart thundered relentlessly.

"I want you, Rin," he whispered.

"I do, too," she murmured. "But I . . . I can't. Ring's your—"

Then, his mouth covered hers. She let him do it, closing her eyes and letting him close the distance between them. His hand lay on her stomach, warm through the thin shirt she wore as a pyjama top, starting to inch slowly upward. Rin didn't want to stop him, but Ring came through her mind, the blue-haired girl's kind smile, making Rin feel sick. She started to draw away, but he pulled her back in, knocking her sharply onto the ground and pinning her roughly. But she didn't care. She couldn't give him up, not now, not when he was kissing her.

And then, Rin heard the doorbell and was forced to swiftly push Lui off her as her brother opened the front door, his voice joined by Ring's. Rin couldn't look at Lui for the rest of the night, even though she could feel him searching for her gaze. As Ring smiled and hugged her, exclaiming about how worried she was, Rin felt sick. How could she do something so terrible to someone so sweet? Ring deserved so much better.

. . .

"What are you doing here?" Rin questioned as she opened the door the next day to Lui and Lui alone. To avoid catching her brother, Len's, attention, she rushed out onto the street, closing the door behind her. She glanced into the car sitting behind Lui. "Where's Ring?"

"You said we'd go to the arcade today, remember?" he stated.

"But, after that . . . ." She trailed off, unable to finish the sentence. She averted her gaze, her cheeks going bright red.

"I really meant what I said, Rin," he murmured, taking her hand gently and pushing a stray lock of her hair behind her ear. She shivered at the feel of his hands on her face. "You're the one who I want, not Ring."

"But that's not fair to her," she whispered, still unable to look at him for fear of being taken captive by his gaze. "She's your girlfriend, not me."

"I don't care, Rin," he insisted, pulling her sharply toward him. His lips mashed against hers, and tears gently trickled down her cheeks. She hated how much she wanted him, how good this felt. It wasn't fair, not to Ring, and it wasn't fair to Rin. He pulled away, and she met his passionate gaze as he announced, "I want _you_, Rin!"

"But Ring—" she whispered, almost begging.

"She doesn't matter, Rin," he argued. "She doesn't have to know."

"Lui," Rin whispered, unable to resist as she hid her face in his shirt, hugging tightly onto him, her fingers choking the fabric of his shirt. "I love you so much, Lui. I need you."

He responded by kissing her again, more fiercely than before. He grabbed her by the shoulders and leaned her against his car, kissing her with so much yearning. She wanted to give him everything he wanted. She loved him so much. It wasn't fair that Ring had gotten to him first.

. . .

At the end of the day, when the arcade was closing and Rin had managed to beat all of Lui's records, as promised, Rin tentatively took hold of Lui's hand as they walked out of the building. He smiled at her, and she smiled shyly in return. She climbed into the passenger seat of his car, watching him as he began to drive. Then, slowly, she dared to ask, "Where are we going now?"

"My place," he replied, glancing at her. "Is that okay?"

Rin nodded, though the thought worried her a bit. Was he expecting . . . _that_ from her? He lived by himself, so they wouldn't have to worry, but Rin wasn't sure if she was ready for that yet.

She didn't have time to think about it for long before her phone vibrated in her pocket. She could feel Lui watching her carefully as she answered it.

"Hey, Rin, wanna hang out?" Ring questioned right off the bat.

"R-Ring?" Rin stuttered, immediately being brought back to reality.

"Yeah, I was supposed to be on a date with Lui all day but he cancelled on me. Something came up last minute, apparently. Boo. Oh well. Now we can hang out, right?"

"A-actually, I can't," Rin said, staring at Lui, who continued to watch her as best he could as they drove. "I'm kinda out somewhere right now."

"Boo, you loser. C'mon. We could have a sleep over. Just come over once you're done."

Sleep over? She stared at Lui. She hated to do this, but it was a perfect excuse. "Yeah, okay. I'll be over later."

"Yay! Love ya, Rin! Talk to you later!"

"Bye," Rin mumbled, hanging up the phone and immediately dialling another number. Her brother picked up the other line. "I'm sleeping over at Ring's tonight, okay?" She hung up without waiting for a response.

Lui didn't say anything more.

. . .

"L-Lui!" she gasped as he mashed his mouth against hers the moment the car parked behind his apartment building. She pulled her head back, gasping in a breath. She stared at him harshly. "Wait a minute! I don't want to do this is your car!"

"Why does it matter where we kiss?" he wondered, scowling. "All that matters is that it's just the two of us, right?"

"I don't want to risk anyone we know seeing us," she insisted, glancing out the windows cautiously.

"That's exactly what you said at the arcade," he stated, his voice a little whiney. "If you won't do it here, will you at least come upstairs?"

"I'm going to see Ring," Rin replied stubbornly. Ring and Lui lived in the same apartment building, just a couple floors standing between them.

"Please, Rin," he whispered, leaning forward and breathing gently against her ear, causing her to shiver. "I want _you_. Please." She gasped in shock as she felt something wet trail itself along her ear. It felt odd, but her body told her that she liked it. She closed her eyes and craned her neck to offer easier access, asking for more. His lips began to trail along her neck.

"Just a little," she whispered, knowing full well that she was playing right into his trap but unable to care. "I'll come up for just a little."

With a self-satisfied smile, he led her upstairs, tugging her into his apartment on the fourteenth floor. His apartment was small but tidy. She gently placed her bag on top of a table and peered around as he flicked the lights on. Rin stared at a picture of the three of them, her, Lui, and Ring, on his coffee table. Lui and Ring were holding hands. It wasn't fair. It just wasn't fair.

"Want to watch a movie?" Lui wondered, taking a seat on the apartment's couch.

"Only if it's not some sappy, romantic one," Rin countered, smirking. "I'm sure your apartment is full of those, huh?"

"I would've assumed you'd say that about porn, but whatever," he replied, smirking back.

Rin's face went bright red and she sat beside him, stating, "None of that, either."

"Are you sure? I've got some really good ones," he teased.

"You're terrible," she stated, narrowing her eyes at him. "What girl in her right mind would want to watch porn with you?"

Then, Rin couldn't help but realize that they were completely, utterly alone. She felt so guilty now. Ring. This wasn't fair to Ring. Still, slowly, slowly, their faces moved closer together. Rin closed her eyes and closed to distance, pressing her lips against his, the boy she loved. He lowered her against the couch, his mouth prying hers open as they came into rhythm with each other. His hand slid onto her stomach, this time under the fabric of her shirt, and came into contact with her bra. She squeaked in shock as he grabbed onto what lay underneath. His hands grabbed onto the fabric of her shirt and pulled it up, over her head. She stared at him, seeing that hunger in his gaze. She knew what he wanted.

"No," she murmured, placing her hands against his chest and pushing him away.

"Why not?" he wondered, staring at her like she was the only one in the world.

"Ring," she whispered.

"Don't you love me, Rin?" he questioned.

"I do, Lui, but I . . . ."

"Please, Rin, if you love me, then can't you please just do this for me?" he begged. "I want you so badly."

"But if I don't go home, my parents will know that something happened."

"You said you'd be at Ring's, right? That's the perfect alibi."

"But Lui . . . ."

"Please, Rin," he begged, looking at her and only her. "This is all I ask for of you."

As she gazed into those eyes, she couldn't say no. "Will you break up with Ring?" she challenged.

"Yes, I will."

Rin squeezed her eyes shut. This felt so terrible, but she loved him. She didn't want him to hate her. She wanted to make this love of theirs last. So, she stood up, leaving him on the couch, and reached behind her back. She tore off her bra, staring at him as she did, his eyes gleaming as he watched, and dropped it on the ground.

"If it's you, I'll show you everything. You can have all of me," she whispered. "But only if you'll be mine and mine alone."

"I will, Rin," he whispered back, standing up and gliding over to her. Then, he took her hand and pulled her over to the bedroom, pinning her onto the bed. Rin loved it and hated it simultaneously, but she loved Lui too much to refuse him. She let him do whatever he wanted, and, in return, she did everything he asked of her. She really loved him, and now she knew that he loved her, too.

. . .

Rin opened her eyes the next morning as she heard a loud clang. Blearily opening her eyes, she felt a little strange. She sat up in bed, looking around to see what had made the noise. She awoke immediately when she did.

"Ring!" she exclaimed, realizing then that her clothes were gone, strewn across the apartment. She pulled the blanket up to cover her chest.

Ring, a fallen pot at her feet, stared at her, her expression unreadable. Rin reached desperately for Lui's hand, needing his reassurance, but her hand fell through the air, and, when she looked, he was gone.

"What's going on here?" Ring questioned coldly.

"Ring, I'm so sorry," Rin begged, feeling even more helpless as her lack of clothes bound her to the bed.

Then, Ring strode over to her, and the sound of a slap rang through the air. Rin gasped sharply, holding a hand to her cheek as it pulsed in agony. Then, Ring shouted, "What the hell are you doing here, Rin? I was so worried when you didn't show up, and now . . . now . . . . Did you sleep with him, Rin? Did you?"

"Y-yes," Rin stuttered, unable to lie to her friend.

"He's my boyfriend!" Ring exclaimed. "How could you do this to me, Rin?"

"Rin? Ring?" Lui entered, fully clothed, behind Ring. Rin looked at him desperately. Ring turned her vicious, heartbroken glare onto him.

"What the hell is this, Lui?" the blue-haired girl shouted. "You couldn't think of any way crueler to break up with me than this?"

"How did you get in here?" he challenged, horrified.

"You left the door unlocked, moron!" she replied. "Are you breaking up with me?"

"No, never!" he insisted, grabbing her by the shoulders and forcing her to stare into his eyes. He was so desperate. "I truly love you, Ring! Honestly! I just . . . I just . . . . Look, I don't know! Rin was just a mistake, okay? Please, Ring. I love you so much."

"Lui," Rin whispered, tears falling from her eyes. "But you said . . . ."

"Get out," came Ring's voice. Then, she turned and landed her blue eyes on Rin's. "Get out, get out, get out! You're not welcomed here anymore! Stay far away from me, forever! I hate you, Rin!"

"I'm so sorry," Rin whispered, looking to Lui, but he refused to meet her gaze.

"If you were really sorry, you never would have done it," Ring retorted.

Rin felt so terribly sick.

**Author's Note: Just so you know, Ring didn't just forgive Lui, she just wants Rin out before she yells at him. Take notice that Lui only ever said he wanted Rin, not that he loved her. Well, please review!**


End file.
